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Write a response that appropriately completes the request.

### Instruction:
What is the major contribution of the philosopher Immanuel Kant?

### Response:
assistant
Immanuel Kant is best known for his theory of universal moral law, the categorical imperative, which states that one should always act in a way that can be willed as a universal law. He is also known for his concepts of the transcendental unity of apperception, the sublime, and his critiques of rationalist and empiricist philosophy.